Iranian Nobel Peace laureate Shirin Ebadi has warned the United Nations that an Iranian government crackdown on the opposition protests planned to coincide with the anniversary of the Islamic Republic on February 11 could "bring about a catastrophe."

In an open letter to the United Nations Human Rights Council, Ebadi wrote that if the opposition activity sparked by June's disputed presidential election is crushed by the government, the country's growing social unrest "may undermine peace and security in Iran, if not in the entire region."

Ebadi urged the UN council to appoint a special investigator for Iran.

The 47-member council is to hold a three-hour review of Iran's human rights politics on February 15.